Automated optical inspection of motor vehicles with the aid of video cameras is available.
An object of the present invention is to provide an improved device and an improved method for the automated testing of vehicles, in particular motor vehicles.
This object may be achieved by an example method and example device according to the present invention.
The example method according to the present invention for testing a vehicle includes driving the vehicle over a measuring device, and recording the sound emitted by the vehicle during the drive-over using a sound recording device (microphone) and evaluating the recorded sound for vehicle diagnosis.
An example device according to the present invention for testing a vehicle has at least one sound recording device and one evaluation device. The sound recording device is designed for recording sound which is generated and emitted by a vehicle to be tested. The evaluation device is designed for evaluating the sound recorded by the at least one sound recording device for vehicle diagnosis.
An example method according to the present invention and an example device according to the present invention may make improved vehicle diagnosis possible by evaluating the sound emitted by the vehicle to be tested and identifying abnormalities in this sound which point to an error of the vehicle.
The automated recording and evaluation of sound which is emitted during operation of the motor vehicle by the engine, the exhaust system and/or the articulations, are presently not heretofore known.
A motor vehicle diagnosis according to the present invention may be carried out reliably and in automated form. The result is in particular not dependent on the skills and the experience of a motor vehicle mechanic carrying out the diagnosis, who evaluates the noises emitted by the vehicle “by ear.”
In one specific embodiment, a method according to the present invention includes comparing the recorded sound with a predefined setpoint sound and identifying deviations of the recorded sound from the predefined setpoint sound. An ideal, perfectly functioning vehicle generates setpoint sound, which in particular includes the noises of the running internal combustion engine, including the exhaust gas system, caused by possible vibrations of components on the vehicle and the noise of the rolling motion of the tires.
Defects in the internal combustion engine or the exhaust gas system, unfastened or loose components and/or defective tires cause additional noises or deviating noises in the actual sound, so that this sound deviates from a setpoint sound which is emitted by an ideal vehicle having no defects. This makes it possible to detect defects in the vehicle by determining the difference between the recorded actual sound and the predefined, ideal setpoint sound.
In one specific embodiment, the evaluation of the recorded sound includes identifying abnormalities in the recorded sound. This makes an automated vehicle diagnosis possible even when the setpoint sound of an ideal vehicle is not known. Abnormalities may be identified, for example, with the aid of so-called statistical learning methods.
In one specific embodiment, the method includes recording at least one optical image of the vehicle and optically representing at least one located sound source in at least one recorded image. This makes it possible to locate sound sources which are possibly caused by defects particularly well and conveniently. The combination of the acoustic evaluation with optical images of the vehicle makes it possible to improve and simplify the evaluation and error diagnosis even further, since it is directly identifiable in the combined image at which point of the vehicle the troubleshooting is be continued.
In one specific embodiment, the method includes locating at least one sound source on the vehicle. Locating the source(s) of noises contained in the recorded sound, e.g., with the aid of directional microphones, makes it possible to improve the quality of the diagnosis, since the sound sources and accordingly defects, which generate unusual noises, may be spatially located. The further troubleshooting may then be concentrated on the identified located and spatially limited area.
In one specific embodiment, a device according to the present invention has at least two sound recording devices (microphones). A plurality of sound recording devices makes it possible to locate the sound sources on the vehicle in a particularly good and effective manner.
In one specific embodiment, the sound recording devices are designed in such a way that good locating of the sources of the recorded sound is made possible. The sound recording devices may in particular be designed as directional microphones. By locating the sound sources precisely, the causes of possible defects may be narrowed down particularly well, and the troubleshooting is simplified and accelerated.
In one specific embodiment, a device according to the present invention includes at least one image recording device, which is designed for recording at least one image of the vehicle to be tested.
In one specific embodiment, a device according to the present invention includes an evaluation device, which is designed for representing the source(s) of the recorded sound in at least one image of the vehicle to be tested.
The present invention is explained below based on the figures.